Computer turns on but monitor does not display and mouse and keyboard dont light up

[123wil82]

Today I was switching coolers. The fans and case light turned on. the cpu wasn't hot but no display to monitor and keyboard did not turn on. I saw that that the top right of my keyboard would slightly light up if a pressed a key. If I plugged in the mouse then it would light up and turn off a second later. I don't think it's my power supply because it worked before I was swapped coolers. Thanks

 

[CountMike]

It's obvious you did something wrong during cooler installation so go back to it and check everything.

 

[123wil82]

It's obvious you did something wrong during cooler installation so go back to it and check everything.

That's what i thought but i reinstalled the cooler multiple times and if the cpu was over heating then wouldn't the computer just turn off a couple seconds after i started it up.

 

[CountMike]

Cleaned up old paste with alcohol, applied new paste ? Intel or AMD ? Standard or aftermarket cooler ?

 

[123wil82]

Cleaned up old paste with alcohol, applied new paste ? Intel or AMD ? Standard or aftermarket cooler ?

I cleaned with a paper towel not alcohol. I put on new paste. I even tried cleaning again and re applying paste. Its AMD and i was switching from a aftermarket cooler to a standard because i wanted to sell the computer.